Fire in the hole

{{short description|Colloquial saying}}

{{Other uses}}

"Fire in the hole" is an expression indicating that an explosive detonation in a confined space is imminent. It originated from American miners, who needed to warn their fellows that a charge had been set.{{cite web|title=Fire in the hole|url=http://www.word-detective.com/2008/10/fire-in-the-hole/|publisher=The Word Detective|date=October 10, 2008|access-date=2013-07-30|archive-url=https://web.archive.org/web/20130804023953/http://www.word-detective.com/2008/10/fire-in-the-hole|archive-date=2013-08-04|url-status=dead}} The phrase appears in this sense in American state mining regulations,{{Cite web|url=https://www.ilga.gov/commission/jcar/admincode/062/062002250000550R.html|title=Section 225|website=Ilga.gov|access-date=3 April 2021}}{{cite web|url=http://adminrules.idaho.gov/rules/2011/17/0803.pdf|title=Idaho Administrative Code}} in military and corporate procedures,{{cite web|url=https://www.patrick.spaceforce.mil/?id=123409836|title=Here comes the boom|access-date=2014-10-20|archive-url=https://web.archive.org/web/20141102025848/http://www.patrick.af.mil/news/story.asp?id=123409836|archive-date=2014-11-02|url-status=live}}{{cite web|url=https://www.nsf.gov/about/contracting/rfqs/support_ant/docs/mgt_manuals/mcm/blastingsop-499.pdf|title=Blasting Standard Operating Procedure, Raytheon Polar Services Company|access-date=2014-10-20|archive-url=https://web.archive.org/web/20140824071333/http://www.nsf.gov/about/contracting/rfqs/support_ant/docs/mgt_manuals/mcm/blastingsop-499.pdf|archive-date=2014-08-24|url-status=dead}} and in various mining and military blasting-related print books and narratives,{{Cite web|url=https://www.google.com/search?tbm=bks&hl=en&q=%22fire+in+the+hole%22|title="fire in the hole" - Google Search|website=Google.com|access-date=3 April 2021}}{{Better source needed|reason=The current source is insufficiently reliable (WP:NOTRS).|date=January 2025}} e.g. during bomb disposal or throwing grenades into a confined space.

In common parlance it has become a catchphrase for a warning of the type "Watch out!" or "Heads up!".

NASA has used the term to describe a means of staging a multistage rocket vehicle by igniting the upper stage simultaneously with the ejection of the lower stage, without a usual delay of several seconds. On the Apollo 5 uncrewed flight test of the first Apollo Lunar Module, a "fire in the hole test" used this procedure to simulate a lunar landing abort. Gene Kranz describes the test in his autobiography:{{cite book|first=Gene|last=Kranz|authorlink=Gene Kranz|title=Failure is not an option|publisher=Berkley Books|date=2001|isbn=0425179877|page=215}}

{{blockquote |

The fire-in-the-hole test involved shutting down the descent rocket, blowing the bolts that attached the ascent and descent stages, switching control and power to the ascent stage, and igniting the ascent rocket while still nestled to the landing stage.

| Gene Kranz | Failure Is Not an Option

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